Last night, five women performed a task reserved each year for statesmen, Oscar winners and the regulars of celebrity gossip columns, yet only a few months they were unknown.

The Spice Girls switched on the Christmas lights in London's Oxford Street, the latest piece of exposure in a collective existence spanning less than six months in the public consciousness. If you admit you don't know who they are, your tabloid-reading friends will ask what planet you have been on, but don't be too hard on yourself. In the context of this particular rise, to say "meteoric" would be an understatement.

The exact provenance of the Spice Girls remains unclear. What is indisputable is that their first record, "Wannabe", is at number one in the charts of 27 countries, that it sold 1.25 million copies in the United Kingdom alone and that it stayed at number one here for seven weeks. Their second single, "Say You'll Be There", went straight in at number one and sold 750,000 copies in two weeks and their debut album, Spice, is at number one in Japan and will, without any doubt, go straight to number one when it is released here next week.

What has the music industry in such a sweat over the five women - ranging in ages from 18 to 24 - is that they have succeeded at all. All-girl British groups, apart from the one memorable exception, Bananarama, have always struggled. Five all-singing, all-dancing women were not supposed to be a success - the music press said so when "Wannabe" was released - so what went right?

The secret appears to stem from the fact that these are no puppet airheads. These are feisty women whose sex appeal strikes a chord with teenage boys and men, and whose attitude earns the admiration of young girls and adoring female adolescents.

They claim not to have been put together like their male counterparts in Take That or The Monkees, yet the line-up is suspiciously eclectic.

There is Geri Halliwell, a 24- year-old former Katharine Hamnett model from Watford (the smart one); Melanie Brown, 21 from Leeds, a kick-boxer with a pierced tongue (the tough one); Melanie Chisholm, 20, from Liverpool, who loves football (the tomboy); Victoria Adams, 21, who still lives with her parents and wears stylish clothes (the sophisticated one); and Emma Lee Bunton, 18, from north London, who turns her back on the harder side of the band (the fluffy one).

If you believe their record company, Virgin, the women, who all wanted to be actresses, kept bumping into each other on the television and film audition circuit. They liked each other, decided to share a house together in Maidenhead, Berkshire, to save money, and began writing songs.

If you believe the more sceptical members of the music business, they were brought together as the result of an ad placed in The Stage by a mystery pop Svengali who was pushed aside when the five decided they no longer needed him. Either version ultimately lends itself to the view that they, and not executives, are calling the shots.

"No one really knows for sure how they came together, but they were pushing themselves for a long time," said Selina Webb, managing editor of Music Week. "They would keep appearing at industry parties and people kept saying: `Who are those girls?'.

"They seem to be controlling their own destinies and don't appear to have been manufactured. Their personalities are simply too strong. Perhaps there was someone in the beginning who brought them together, but they are definitely calling the shots now."

Muff Fitzgerald, their spokesman at Virgin, said the band independently approached Simon Fuller, who manages Annie Lennox.

"They went to Simon because they respected Annie and he was simply bowled over by their music," he said. "The whole thing about being put together by someone is just a myth perpetuated by the music press.

"They are pulling the strings here, and that makes some people uncomfortable."